By Don Long

Following a failed attempt to maintain the status of "device" rather than "drug" for its Optison ultrasound contrast agent, Molecular Biosystems Inc. (MBI) this week turned to the courts to pursue its competitive edge via patent contest.

Last week, the FDA determined that MBI's Optison FS069 — approved in February by the Radiological Devices Advisory Committee of the FDA as a device — now will have to be evaluated by the Center for Drug Evaluation and Research, thus putting it in the same category as competing agents.

Manufacturers of those competing agents, all still in development phases, had forced that ruling by filing suit against the FDA via Citizen Petitions charging that the agency had been arbitrary in categorizing Optison as a device, but its products as drugs. Filing the suits were Sonus Pharmaceuticals Inc., of Bothell, Wash., Bracco International B.V., of Princeton, N. J., and DuPont Merck Pharmaceutical Co., of Wilmington, Del., which claimed that MBI's Optison should be put in the same category to provide a level field for all market players.

Following the FDA's decision, MBI last week, in conjunction with marketing partner Mallinckrodt Inc., of St. Louis, filed suit in the U.S. District Court for the District of Columbia against five companies termed "potential competitors," in an attempt to invalidate the patents on their ultrasound contrast agents. The suit was filed against Sonus, Bracco and ImaRx Pharmaceutical Corp., of Tucson, Ariz., along with its marketing partner, DuPont Merck, and Nycomed Imaging AS, of Oslo, Norway.

Additionally, the company filed petitions with the U.S. Patent and Trademark Office requesting it re-examine patents held by Sonus and Nycomed.

The patents held by all of the companies "cover the same alleged invention," according to MBI's chairman, Kenneth Widder. "Under the law, however, only one U.S. patent can issue to any claimed invention," he said.

Additionally, MBI's lawsuit charges that Steven Quay, chairman of Sonus, made false statements intended to damage MBI and its product.

In reply, Quay said his company's "eight U.S. patents directed to fluorocarbon-based ultrasound contrast agents are valid and enforceable. We will vigorously defend that position."

Quay said that the lawsuit by MBI would not impede his company's attempt to seek FDA approval for EchoGen, its ultrasound contrast product whose approval was delayed in late June by the device-or-drug category dispute. *